Irrigation Water Usage Research Articles

Risk efficiency of optimal water allocation within a single- and multi-stage decision-making framework

ABSTRACTThe South African government has put legislation in place to exercise better control over irrigation water usage. Thus, proper planning of irrigation areas and scheduling of irrigation events in order to stay within water quotas has become more important. Currently, the available methodologies to assist irrigation farmers overlook the complexities and interrelated relationships between crop-area planning and the multi-stage nature of irrigation-scheduling decisions within a stochastic dynamic environment. This paper contributes to knowledge through the development of a bio-economic model that uses evolutionary algorithms to optimise water use, taking cognisance of the complex interrelationships between crop-area planning, the multistage decision-making nature of irrigation-scheduling decisions, and the stochastic dynamic environment under conditions of limited water supply. The results show that gross margin variability is reduced and the expected outcomes are improved due to improved irrigation-scheduling decisions made sequentially in multiple stages. Multi-stage decisions tend to make the impact of risk aversion less profound because taking account of unfolding weather information is risk reducing. Ignoring the risk-reducing impact of sequential decision-making will over-estimate the cost of water restrictions. Caution is hence necessary when formulating agricultural water-allocation policies based on crop water optimisation models that overlook the complex nature of irrigation decisions.

Surface and Volume Variation Determination of Laguna de Laja (Chile) since 2007

Abstract. The present work aims to determine surface and volume variations of Laguna de Laja using satellite imagery (Landsat), image processing techniques, a digital bathymetric model and in situ measurements. Laguna de Laja, one of the mayor hydrologic resources in Chile is located at about 600 km to the south of Santiago de Chile, Chiles capital city, in the Andes mountains. Its particularity is caused by Tourism – as it is located in the vicinity of the Laguna de Laja National Park Irrigation – 120000 hectares Hydroelectric power generation – 4 mayor power plants For this study, Landsat 5, 7 and 8 were considered. A total of 47 satellite images were acquired for March, June, September and December since 2007. The bathymetric model of the Laguna de Laja was generated in 2001 in a scientific research collaboration between the University of Concepción (Chile) and the German Research Center for Environmental Research (Germany). A single beam echo sounder EA400 in combination with a Trimble GPS 4000 SSi receiver was used to survey the Laguna de Laja. One of the fundamental steps on which is based our approach makes use of the Normalized Difference Water Index (NDWI), which considers the green and near infrared bands of Landsat. The calculation of this index allows to separate water bodies from any other type of surface coverage (McFeeters, 1996). In our case the Laguna de Laja has a quite irregular form but it is embedded in a mountainous area. In consequence it can easily be detected by the generation of density slices based on NDWI. Our results indicate that the Laguna de Laja suffers a permanent loss of water. Nevertheless there is no linear trend observable. Between 2010 and 2013, a constant loss in both surface (2 cukm) and volume (32 sqkm) can be detected. Furthermore, between 2014 and 2016, water volume increased in both surface and volume. Since 2017 seasonal maxima (December) and minima (June) are clearly defined and almost no loss has occurred since. In totaled considering the observed time span surface diminished by 20,3% and water volume loss is 24,5%. Future work has to be focused on the sources for the indicated loss of water. Many reasons, such as higher temperatures, increase in water usage for irrigation, decrease of precipitation, and many others.

Simulating Potential Weekly Stream and Pond Water Available for Irrigation in the Big Sunflower River Watershed of Mississippi Delta

Groundwater storage and level have declined rapidly in the Big Sunflower River Watershed (BSRW) of Mississippi Delta in recent years. Farmers in this region are beginning to save groundwater resources by increasing surface water usage for agricultural irrigation. In this study, we estimated the weekly amount of surface water available in ponds and streams, determined if the weekly surface water resources are sufficient for major crop irrigation demand, and assessed how much surface water can replace groundwater for agriculture irrigation in the BSRW. The SWAT (Soil and Water Assessment Tool) model was employed to simulate the weekly water resources for 23 sub-basins from the BSRW. Results showed that weekly stream water resources (SWR), stream evaporation (SE) and water loss from the channel via transmission through the side and bottom of the channel (stream transmission, referred as ST) for BSRW during the growing seasons ranged from 20.4 to 29.4 mm, 7.4 to 14.4 mm, 1.6 to 4.5 mm and 1.1 to 1.6 mm, while pond water resources (PWR) and pond evaporation (PE) ranged from 1.9 to 2.1 mm and 0.3 to 0.5 mm. The value of SWR − (ST + SE) and PWR − PE were positive in all sub-basins, indicating that there are net surface water resources available in this region. The percentages of total groundwater usage for irrigation that could be replaced by surface water in each sub-basin every week of each month from May to September ranged from 10% to 87%. Our studies suggested that the conjunctive use of surface and groundwater for agriculture irrigation is a feasible method for groundwater sustainable management in the Mississippi Delta.

Dynamics of Water Quality: Impact Assessment Process for Water Resource Management

Surface water is an important source of water supply for irrigation purpose and in urban areas, sewage water is being disposed of in nearby canals without treatment. A study was conducted to investigate the dynamics of water quality of irrigation canal as a result of this practice. The study ascertained the impact of different salinity parameters, indices and approaches to examine the hazardous effects on quality of canal water. The study analyses the samples collected for various parameters like pH, TDS, EC, Na, Cl, Ca, Mg, K, CO3, HCO3 etc. It helped to decide the restriction on use of water based on FAO-UN guidelines. Investigations were focused on assessment of contaminants affecting the quality of water and having hazardous effects on different stages of irrigation water usage. Wilcox diagram and Doneen’s approach-based analysis helped to identify the class and quality of water. This study shall help to analyze the quality of water and provide support to the decision makers for better water resource management and policy development for irrigation purpose i.e., treatment and distribution of water resource.

Carbon Footprint of Rice Production in Indonesia: An Analysis of National Statistics

Estimating carbon footprint (CF) of rice production could administer an insight into the input of rice production to climate change and analysing possible greenhouse gas (GHG) alleviation alternatives. In this study, data for the rice production of 34 provinces in Indonesia at year of 2015 were gathered from the Indonesian statistical data on area cultivation, productivity, fertilizer application, diesel, and irrigated water. The CF of indirect and direct carbon emissions which were correlated with those agricultural intakes was calculated with reported emission factors. The result demonstrated the CFs mean in 34 provinces during dry and rainy season in Indonesia was 1,900,341.48 kg CO eq/ha and 1,892,825.68 kg CO eq/ha, respectively. The data also showed that the highest of CF production during dry and rainy seasons obtained by Belitung Islands and East Nusa Tenggara province, respectively. Meanwhile the lowest of CF production for both dry and rainy season belonged to Yogyakarta province. Result on the quantified agricultural intakes demonstrated the irrigation water usage, fertilizer usage, direct methane and diesel for agricultural tools, had biggest to lowest contribution to CF production, respectively. Based on the result, we concluded that a rice cultivation practices which has an efficient irrigation water usage may become an option to reduce CF that leads to climate change mitigation.

Desain Sistem Manajemen Aset untuk Jaringan Irigasi Tersier

Penelitian ini memaparkan tahap pengembangan sistem informasi untuk manajemen aset irigasi, yang diberi nama Sistem Informasi Management Asset Irigasi-Jaringan Tersier (SIMAI-JT). SIMAI-JT dirancang secara khusus untuk dapat digunakan sebagai alat manajemen pada tingkat jaringan irigasi tersier. Tahap pengembangan SIMAI-JT mencakup desain sistem, pemrograman, dan implementasi. Tahap desain mencakup struktural dan fungsional. Program aplikasi ini didesain dan dikembangkan menggunakan aplikasi VBA di atas platform GIS. Input data ke dalam sistem adalah data spasial dalam format point, poliline dan poligon yang menggambarkan karakteristik komponen dari jaringan irigasi. Data diperoleh dari survey lapangan (menggunakan GPS dan kamera) dan digitalisasi dari peta konvensional yang ada. Selanjutnya, semua data spasial yang diperoleh dikonversi ke layer GIS. Sistem mengintegrasikan dan menampilkan semua layer dalam bentuk foto, citra satelit, dan informasi tabel. Pengujian sistem dilakukan pada HIPPA Sidomulyo, Desa Karangsono, Kecamatan Bangsalsari, di wilayah Kabupaten Jember. Hasil desain dikalibrasi berdasarkan berdasarkan kemampuan dan kebutuhan HIPPA. Hasil menunjukkan bahwa sistem informasi harus dirancang dengan (i) menampilkan peta berbasis citra satelit daerah irigasi, identifikasi dan potensi kerusakan pada jaringan irigasi tersier yang disertai dengan foto bangunan; (ii) kecerdasan buatan (artificial intelligence) dalam penentuan prioritas kerusakan; dan (iii) kinerja kelembagaan. Keluaran program dipergunakan dalam rapat anggota untuk perencanaan strategi kelembagaan dalam penanganan kerusakan jaringan irigasi tersier.

Bridging Farmer and Researcher: Extension through the Eyes of Agents in Rural Pakistan

Irrigation and efficient water usage by farmers remain key agricultural problems in Pakistan. Technological approaches to water management specifically irrigation management using cloud technology is a recent innovation currently being trialed in Pakistan through a project conducted by the authors and funded by the Australian Centre for International Research. The paper reports on the perceptions of rural agents in Pakistan involved in the scaling out of new technologies to improve irrigation practices of a large number of farmers. The methodology adopted the use of focus groups with water professionals and extension agents as this approach has been proven to be a key effective method to assist rural agents to gather current information on irrigation problems and the scaling out process. Eight focus groups were assembled with an average of ten participants in each group. The findings revealed the current practices, positive outcomes and challenges to conducting farmer education in Pakistan. The importance of this research is its potential to improving work practices of large numbers of farmers that continue to be highly challenging. The study gives fresh insights on how farmer education methods could be achieved in relation to improving water irrigation through new technological practices of a significantly increased number of farmers.

Managing food and water security in Small Island States: New evidence from economic modelling of climate stressed groundwater resources

Climate-stressed groundwater resources present a growing challenge for protecting food security and economic sustainability, notably in Small Island Developing States (SIDS). These states are some of the most vulnerable to climate stress because of their large coastlines, vulnerability to rising sea levels, weak access to reliable surface water, and limited food production capacity for handling increased groundwater scarcity. Impacts of climate stressed groundwater resources brought on by irrigation and growing urban demand in SIDS continue to receive widespread attention by both scientists and policymakers. Policies that limit pumping to protect aquifer sustainability reduce short-term economic welfare by unknown amounts that would otherwise be secured by both urban and irrigation water users. Yet, little scholarly research has addressed economic impacts of climate-water stress for the special needs of SIDS for which urban and irrigation pumping compete hydrologically and economically over long time periods. The original contribution of this work is to address that gap by employing downscaled data on precipitation from Representative Concentration Pathways (RCP) climate scenarios. Its novel contribution is to conceptualize, develop, apply, and interpret an integrated hydro-economic framework to understand interconnected physical and economic linkages from managing an unconfined regional aquifer system under each of three climate and two policy scenarios. The application is to Barbados, a SIDS, for which current and future irrigation and urban demands compete for water. The framework integrates groundwater hydrology, climate scenarios, economics, land use, and groundwater management, with the intent to mitigate impacts of climate stress on current economic values of water as well as protecting future aquifer sustainability. Results provide a framework to guide water management for SIDS vulnerable to climate stress for which water of the right quantity, quality, timing, location, and price are essential elements of economic development.

Perspectives for the Development of the Collaboration Relations in the Association Forms for Association Forms in the Galaţi County

Organizing a viable irrigation system in the context of climate change at the level of Romanian agriculture is a priority. Currently, only 12% of the total agricultural area is irrigated. In order to benefit from irrigation, Romanian farmers must be members of the Organization of the Irrigation Water Users (OUAI), assigned to the area in which they own land or conclude seasonal contracts. A survey addressed to the OUAI in Galati County attempted to identify the relations between the members that can lead to the association not only for irrigation, but also for agricultural activities. An analysis of the data obtained from the survey was carried out, using the „fuzzy set comparative qualitative analysis” (fsQCA) method, in the context of land fragmentation, in conjunction with supporting national and European programs for the association and development of the irrigation infrastructure. The results of the study are important because it reflects the main issues highlighted by the farmers in the analyzed area regarding the association.

Web Based Tool to Determine Water Productivity Index and Ph for Managing Paddy Irrigation Water User Group for Tanjung Karang Irrigation Scheme Malaysia

Web Based Tool to Determine Water Productivity Index and Ph for Managing Paddy Irrigation Water User Group for Tanjung Karang Irrigation Scheme Malaysia

Web Based Tool for Managing Paddy Irrigation Water User Group

Web Based Tool for Managing Paddy Irrigation Water User Group

Economics of Water Trading in Consumptive Use

Abstract The economics of water trading in consumptive use has often overlooked the conservation incentives inherent in such trading when institutional rules like prior appropriation govern allocation of water. Utilizing an analytical framework of water trading between two irrigation water users employing irrigation techniques of similar efficiency, the study demonstrates how trade in consumptive use of water reduces incentives for greater diversion by users with prior claims to water, as compared with trade in water diverted. It also shows that such transfer increases the marginal value of water use for those users with junior (priority) claims to water rights. In addition, it explores the applicability of METRIC as a recent innovation in measuring consumptive water use at the field level, lowering the costs of water trading at a smaller spatial scale.

Performance of small-scale irrigation schemes in Lake Tana Basin of Ethiopia: technical and socio-political attributes

ABSTRACTThis study was conducted to investigate technical and socio-political attributes that lead to the underperformance of two selected irrigation schemes (Shina and Bebeks) in the Lake Tana floodplains, Ethiopia. Irrigation application efficiency (AE) at nine experimental fields showed a wide range, from 20 to 80%, but was mostly between 40 and 60%. Irrigation water-use efficiency (IWUE) varied from 1.9 to 7.2 kg m−3 for onion and 0.9 to 1.2 kg m−3 for maize. The lined and earthen canal conveyance losses in Bebeks were 0.037 and 0.047 l s−1 m−1, whereas in Shina they were 0.033 and 0.044 l s−1 m−1, respectively. The overall consumed ratio (OCR) of water was 0.58 for Bebeks and varied from 0.73 to 1.2 in Shina. Both schemes are performing below the standard based on technical performance indicators. Irrigation water user associations (WUAs) were not implemented, but irrigation committees (ICs), composed of local political leaders, are managing both schemes. Canal and reservoir sedimentation from erosion of upstream catchment areas during the rainy season was the major problem.

A New SEBAL Approach Modified with Backtracking Search Algorithm for Actual Evapotranspiration Mapping and On-Site Application

Actual evapotranspiration is one of the most important component for efficient water management and planning. Until recently, evapotranspiration computations and measurements have been performed locally. But, in recent years, actual evapotranspiration computations can be calculated regionally thanks to improvements on remote sensing discipline and satellites. Surface Energy Balance Algorithm for Land (SEBAL) is one of the most commonly preferred technics for actual evapotranspiration mapping. However, this algorithm has some difficulties such as mismatch with Landsat 8 and hot–wet pixel selection which require expert knowledge. In this paper, a novel SEBAL based approach (SEBAL-BSA), which can use Landsat 8 images as data and can automatically perform hot–wet pixel selection using Backtracking Search Algorithm (BSA) with ground control points, has been proposed. SEBAL-BSA was developed and tested using January 22–2015, April 28–2015 and July 01–2015 dated Landsat 8 images in Akarsu Irrigation Water User Association command area in the Cukurova Region of Turkey and actual evapotranspiration mapping was realized without albedo measurements. Accuracy of SEBAL-BSA has been examined by comparing values of predefined ground truth points and values obtained from proposed approach. According to results of parametric matched pairs T test and nonparametric Wilcoxon sign rank test, SEBAL-BSA is highly successful. Applications also show that the SEBAL-BSA is a user-friendly approach for institutions and organizations related to water authorization and management.

Including Farmer Irrigation Behavior in a Sociohydrological Modeling Framework With Application in North India

AbstractUnderstanding water user behavior and its potential outcomes is important for the development of suitable water resource management options. Computational models are commonly used to assist water resource management decision making; however, while natural processes are increasingly well modeled, the inclusion of human behavior has lagged behind. Improved representation of irrigation water user behavior within models can provide more accurate and relevant information for irrigation management in the agricultural sector. This paper outlines a model that conceptualizes and proceduralizes observed farmer irrigation practices, highlighting impacts and interactions between the environment and behavior. It is developed using a bottom‐up approach, informed through field experience and farmer interaction in the state of Uttar Pradesh, northern India. Observed processes and dynamics were translated into parsimonious algorithms, which represent field conditions and provide a tool for policy analysis and water management. The modeling framework is applied to four districts in Uttar Pradesh and used to evaluate the potential impact of changes in climate and irrigation behavior on water resources and farmer livelihood. Results suggest changes in water user behavior could have a greater impact on water resources, crop yields, and farmer income than changes in future climate. In addition, increased abstraction may be sustainable but its viability varies across the study region. By simulating the feedbacks and interactions between the behavior of water users, irrigation officials and agricultural practices, this work highlights the importance of directly including water user behavior in policy making and operational tools to achieve water and livelihood security.

New Comparative Experiments of Different Soil Types for Farmland Water Conservation in Arid Regions

Irrigated farmland is the main food source of desert areas, and moisture is the main limiting factor of desert farmland crop productivity. Study on the influence of irrigation on desert farmland soil moisture can guide the agricultural water resource utilization and agricultural production in those regions. At present, the efficiency of irrigation water usage in Northwest China is as low as approximately 40% of the irrigated water. To understand the response of farmland soil moisture in different soil types on irrigation in the Ulan Buh Desert of Inner Mongolia of China, this experimental study takes advantage of different infiltration characteristics and hydraulic conductivities of sand, clay, and loam to determine an optimized soil combination scheme with the purpose of establishing a hydraulic barrier that reduces infiltration. This study includes three comparative experiments with each consisting of a 100 cm thick of filled sand, or clay, or loam soil underneath a 50 cm plough soil, with a total thickness of 150 cm soil profile. A new type of lysimeter is installed below the above-mentioned 150 cm soil profile to continuously measure deep soil recharge (DSR), and the ECH2O-5 soil moisture sensors are installed at different depths over the 150 cm soil profile to simultaneously monitor the soil moisture above the lysimeter. The study analyzes the characteristics of soil moisture dynamics, the irrigation-related recharge on soil moisture, and the DSR characteristics before and after irrigation, during the early sowing period from 2 April to 2 May 2017. Research results show that: (1) Irrigation significantly influences the soil moisture of 0–150 cm depths. The soil moisture increase after the irrigation follows the order from high to low when it is in the order of loam, sand, and clay. (2) Irrigation-induced soil moisture recharge occurs on all three soil combinations at 0–150 cm layers, and the order of soil moisture recharge from high to low is: clay (54.3 mm, 43.39% of the total irrigation), loam (39.83 mm, 31.83% of the total irrigation), and sand (33.47 mm, 26.75% of the total irrigation). (3) After the irrigation event, DSR below 150 cm occurs for all three soil combinations. This study reveals the characteristics of irrigation-induced soil moisture recharge and DSR, and it shows that farmland consisting of an upper 50 cm plough soil and a lower 100 cm filled clay soil can save more water resource at the study site, which is useful in agricultural control measure and water resource management in arid regions.

Paso Robles vineyard irrigation study provides benchmark data to assist future area groundwater management

Accurate information on irrigation water usage does not exist in many areas where groundwater is the primary water source. This lack of information will hinder efforts to manage these groundwater basins sustainably according to current and future water regulations and policies. Using a low-cost methodology of irrigation-line pressure sensors connected to data loggers, we estimated irrigation applications at 84 vineyard sites in the Paso Robles Groundwater Basin over 4 years (2010–2013). We compared irrigation amounts with the preceding winter's rainfall and with the growing season reference evapotranspiration (ETo). Over the study period, the average annual irrigation application was 11.46 inches (291 millimeters). The average annual application correlated inversely to the preceding winter's rainfall, while the irrigation over the growing season (April–October) correlated directly with the ETo over this same period. This study provides an initial data framework that can be used by groundwater sustainability agencies to help manage groundwater in the Paso Robles area. The methodology also could be utilized in other regions to estimate regional irrigation usage while maintaining anonymity for participants.

Value of irrigation water usage in South Florida agriculture

This study estimates economic loss from South Florida croplands when usage of agricultural irrigation water is altered. In South Florida, 78% of the total value of farm products sold is comprised of cropland products. The majority of Florida citrus and sugarcane are produced in the area, and agricultural irrigation was the largest sector of water use in 2010, followed by public water supply. The Florida Department of Environmental Protection announced in December 2012 that traditional sources of fresh groundwater will have difficulty meeting all of the additional demands by 2030. A shortage of water will impose significant damage to the rural and agriculture economy in Florida, which may lead to higher prices and costs for consumers to purchase citrus or other Florida agriculture products. This paper presents a methodology for estimating economic loss when usage of irrigation water is altered, and examines economic values of irrigation water use for South Florida cropland. The efficient allocation of irrigation water across South Florida cropland is also investigated in order to reduce economic cost to the South Florida agricultural sector.

Deficit irrigation and surface residue cover effects on dry bean yield, in-season soil water content and irrigation water use efficiency in western Nebraska high plains

Considering ground water pumping restrictions and unpredictable amount of water available for irrigation from year to year, Nebraska Panhandle producers are facing a challenge to reduce their irrigation water usage and practice deficit irrigation. Among irrigated crops in the region, dry bean (a major cash crop and critical to crop rotation systems) has relatively low water use and is capable to withstand periods of stress. Consequently, two experiments within six consecutive growing seasons (2010–2015) were conducted to determine the impacts of multiple irrigation scenarios (full irrigation, deficit irrigation, and rainfed) and two soil surface conditions (bare soil versus crop residue) on dry bean production, irrigation water use efficiency, and temporal soil water dynamic within the crop root zone. Dry bean yield ranged from 0.41 to 4.07 Mg ha−1 during the six years of the study (2010–2015). The results (2012–2015) indicated that reducing irrigation water by 25% on average increased irrigation water use efficiency (IWUE) by 26% and only caused 6% yield reduction in relative to the full irrigation treatment scenario. However, applying only 50% crop evapotranspiration requirement (ETc) resulted in significant yield reduction (30% reduction on average) in 5 out of 6 years compared to the full irrigation treatment (p < 0.05). Our results indicate that temporal in-season rainfall and ETc demand variabilities along with the per-season soil water content status should be carefully analyzed in order to target the appropriate growth stage(s) for more severe deficit irrigation scenarios. When pre and early season rainfall was abundant deficit irrigation treatments imposed before flowering outperformed treatments targeting after flowering. However, under normal and dry conditions yield decline was more pronounced due to severe early season (before flowering) water stress compared to late season (after flowering) water stress. In two of three years plots with bare soil significantly (p < 0.05) outyielded plots covered with residue. Average yield across irrigation treatments was 14% lower for plots with residue cover (average yield: 2.15 Mg ha−1) compared to bare soil plots (average yield: 2.51 Mg ha−1). Overall, the dynamic of soil water content within root zone and IWUE in plots covered with residue was similar to that in bare soil plots across irrigation treatments throughout the growing seasons.

English

Assessment of irrigation performances is very essential while planning and chalking out management strategies for various irrigation. However, in Ethiopia, especially Tigray, performance evaluation of irrigation schemes is rarely conducted. The performance of Tahtay Tsalit irrigation scheme was not assessed yet and hence, this research was undertaken to assess the hydraulic performance of the irrigation scheme. The study was carried out during the irrigation season from September to November, 2016. The field measurements on canal dimensions, water flow measurements and water surface elevation were undertaken at selected sampling points. Simple descriptive statistics was employed for analysis of the data collected from field measurements and observations. However, hydraulic performance indicators were used to evaluate the performance of this irrigation scheme. Several factors such as flooding, sedimentation, design problems, damage of sluice gates, abstraction of irrigation water by unwanted plants has been identified in this irrigation scheme for mal-functional of different irrigation structures. Hydraulic performance of the irrigation system was evaluated using ten hydraulic performance indicators. There was no problem in irrigation adequacy (0.84 fair), equity (fair), dependability (0.057 good) and efficiency (0.77 fair) of irrigation water in this irrigation scheme. The average water surface elevation ratio, delivery performance ratio, and delivery duration ratio of the main canal during the monitoring period was less than one, greater than 5 and 150%, respectively. The highest sediment accumulation was observed at head and middle reaches of the irrigation scheme than the tail reaches. Generally, in this irrigation scheme there were a number of irrigation structures which had mal-functioned, and now required to be remodeled with sustainable solution to improve the performance of the irrigation scheme. Hence, it has been recommended that capacity building and awareness creation for irrigation water users, water committee, Woreda and Kebelle expertise are the main key factor to bring a change in irrigation water managements. Key words: Hydraulic structures, hydraulic performance, small scale irrigation scheme.